/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package hivemall.tools.array;

import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;

import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.UDF;
import org.apache.hadoop.hive.ql.udf.UDFType;
import org.apache.hadoop.io.IntWritable;

@Description(name = "sort_and_uniq_array",
        value = "_FUNC_(array<int>) - Takes array<int> and "
                + "returns a sorted array with duplicate elements eliminated",
        extended = "select sort_and_uniq_array(array(3,1,1,-2,10));\n" + "> [-2,1,3,10]")
@UDFType(deterministic = true, stateful = false)
public class SortAndUniqArrayUDF extends UDF {

    public List<IntWritable> evaluate(List<IntWritable> ary) {
        Set<IntWritable> s = new TreeSet<IntWritable>(ary);
        return new ArrayList<IntWritable>(s);
    }

}
